22,305 research outputs found
CE Challenges: Work to Do
CE has been used for more than two decades now. Despite many successes and advantages, there are still many challenges to be addressed. These challenges are both technical and organisational. In the paper we will address the current challenges of CE. Many challenges are related to the exchange of data and knowledge and to the systems that make data and knowledge exchange possible. Although much progress has been made in enabling extensive data and knowledge exchange and use, much remains to be wished. For example, there are still barriers to data exchange. Technically, these barriers may consist of different formats, differences in infrastructures and systems, and different semantics. There are also organisational and political barriers. For example, investment in information system may heavily impact upstream suppliers, while revenues of better information exchange may predominantly be gained by downstream actors. Without sharing costs and revenues, chain-wide information exchange will not be easily realised. Another barrier is the possible lack of willingness to share information, because of potential misuse of knowledge and loss of power. The paper is organised as follows. First we will describe the current manifestation of CE as described in a recent book. Second, we will list current trends in CE. Third, we will present some Critical Success Factors (CSFs) that are considered relevant for implementing and adapting CE practices. Last, we indicate some research and practical questions to be addressed, especially for areas that have a high potential and actual impact. </p
Historically unprecedented Northern Gulf of Mexico hurricane activity from 650 to 1250 CE
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Rodysill, J. R., Donnelly, J. P., Sullivan, R., Lane, P. D., Toomey, M., Woodruff, J. D., Hawkes, A. D., MacDonald, D., d'Entremont, N., McKeon, K., Wallace, E., & van Hengstum, P. J. Historically unprecedented Northern Gulf of Mexico hurricane activity from 650 to 1250 CE. Scientific Reports, 10(1), (2020): 19092. doi:10.1038/s41598-020-75874-0.Hurricane Michael (2018) was the first Category 5 storm on record to make landfall on the Florida panhandle since at least 1851 CE (Common Era), and it resulted in the loss of 59 lives and $25 billion in damages across the southeastern U.S. This event placed a spotlight on recent intense (exceeding Category 4 or 5 on the Saffir-Simpson Hurricane Wind Scale) hurricane landfalls, prompting questions about the natural range in variability of hurricane activity that the instrumental record is too short to address. Of particular interest is determining whether the frequency of recent intense hurricane landfalls in the northern Gulf of Mexico (GOM) is within or outside the natural range of intense hurricane activity prior to 1851 CE. In this study, we identify intense hurricane landfalls in northwest Florida during the past 2000 years based on coarse anomaly event detection from two coastal lacustrine sediment archives. We identified a historically unprecedented period of heightened storm activity common to four Florida panhandle localities from 650 to 1250 CE and a shift to a relatively quiescent storm climate in the GOM spanning the past six centuries. Our study provides long-term context for events like Hurricane Michael and suggests that the observational period 1851 CE to present may underrepresent the natural range in landfalling hurricane activity.Funding for this project was provided by the Strategic Environmental Research and Development Program (SERDP) grant and NSF awards 0903020, 1902463, and 1854980 awarded to Jeffrey Donnelly, and the USGS Land Change Science Program
Synthesis optimization and charge carrier transfer mechanism in LiLuSiO<sub>4</sub>:Ce, Tm storage phosphor
LiLuSiO4:Ce and LiLuSiO4:Ce, Tm show very efficient charge carrier storage properties upon beta irradiation after samples have received treatment in vacuum. They outperform the commercial storage phosphor BaFBr(I):Eu2+ in many aspects. The influence of the synthesis conditions, Ce and Tm concentration, nonstoichiometry and codoping with Ca, Hf, Al and Ge are reported. Based on the results of the synthesis optimization, thermoluminescence (TL) emission and TL excitation spectra a mechanism of charge carrier transfer, storage, and recombination during irradiation and thermal or optical readout is proposed.Accepted Author ManuscriptRST/Fundamental Aspects of Materials and EnergyRST/Luminescence Material
The impact of P(NDI2OD-T2) crystalline domains on the open-circuit voltage of bilayer all-polymer solar cells with an inverted configuration
We fabricated P(NDI2OD-T2)/PTB7 bilayer all-polymer solar cells with an inverted configuration, where the annealing temperature was systematically varied. The current density-voltage behavior was investigated and the structural properties of the P(NDI2OD-T2) layers were characterized. Absorption spectroscopy, surface morphology, and crystallite analysis showed that increasing phase segregation of P(NDI2OD-T2) films occurred as the annealing temperature increased. We found that, as the P(NDI2OD-T2) stacking improved, with larger domains, the open-circuit voltage decreased and the saturation dark current density increased. This work provides a guide for the processing of P(NDI2OD-T2) layers to maximize the power conversion efficiency of all-polymer solar cells. (C) 2015 Author(s).open1186sciescopu
Data and code for: Variational Graph Author Topic Modeling
This is the tensorflow implementation of KDD-2022 paper "Variational Graph Author Topic Modeling" by Delvin Ce Zhang and Hady W. Lauw.
VGATM is a Graph Neural Network model that extracts interpretable topics for documents with authors and venues. Topics of documents then fulfill document classification, citation prediction, etc.
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Updated analytical solutions of continuity equation for electron beams precipitation – I. Pure collisional and pure ohmic energy losses
We present updated analytical solutions of continuity equations for power-law beam electrons precipitating in (a) purely collisional losses and (b) purely ohmic losses. The solutions of continuity equation (CE) normalized on electron density presented in Dobranskis & Zharkova are found by method of characteristics eliminating a mistake in the density characteristic pointed out by Emslie et al. The corrected electron beam differential densities (DD) for collisions are shown to have energy spectra with the index of −(γ + 1)/2, coinciding with the one derived from the inverse problem solution by Brown, while being lower by 1/2 than the index of −γ/2 obtained from CE for electron flux. This leads to a decrease of the index of mean electron spectra from −(γ − 2.5) (CE for flux) to −(γ − 2.0) (CE for electron density). The similar method is applied to CE for electrons precipitating in electric field induced by the beam itself. For the first time, the electron energy spectra are calculated for both constant and variable electric fields by using CE for electron density. We derive electron DD for precipitating electrons (moving towards the photosphere, μ = +1) and ‘returning’ electrons (moving towards the corona, μ = −1). The indices of DD energy spectra are reduced from −γ − 1 (CE for flux) to −γ (CE for electron density). While the index of mean electron spectra is increased by 0.5, from −γ + 0.5 (CE for flux) to −γ + 1(CE for electron density). Hard X-ray intensities are also calculated for relativistic cross-section for the updated differential spectra revealing closer resemblance to numerical Fokker–Planck (FP) solutions
Introduction and Author Biographical Notes
The Introductory Notes include The Cutting EDge\u27s mission statement, editorial board, founder\u27s note, and author\u27s biographies
From the Editors and Author Biographical Notes
Letter from the Editors and Author Biographical Note
Surface modification with MK-2 organic dye in a ZnO/P3HT hybrid solar cell: Impact on device performance
The photovoltaic performance of a hybrid ZnO/P3HT heterojunction was improved by modifying the device surface with the MK-2 dye. This organic dye enhanced the compatibility between the polymer and the metal oxide, increased the exciton separation efficiency, and improved the molecular ordering in the charge transport network. The resulting device displayed a substantial enhancement in the photocurrent, open circuit voltage, and fill factor, leading to a 12-fold increase in the power conversion efficiency relative to the unmodified device, from 0.13% to 1.53%. (C) 2014 Author(s).open1145sciescopu
The Warwick patellofemoral arthroplasty trial : a randomised clinical trial of total knee arthroplasty versus patellofemoral arthroplasty in patients with severe arthritis of the patellofemoral joint
Background
Severe arthritis of the knee is a disabling condition, with over 50,000 knee replacements performed each year in the UK. Isolated patellofemoral joint arthritis occurs in over 10% of these patients with the treatment options being patellofemoral arthroplasty or total knee arthroplasty. Whilst many surgeons believe total knee arthroplasty is the 'gold standard' treatment for severe knee arthritis, patellofemoral arthroplasty has certain potential advantages. Primarily, because this operation allows the patient to keep the majority of their own knee joint; preserving bone-stock and the patients' own ligaments. Patellofemoral arthroplasty has also been recognised as a less 'invasive' operation than primary total knee arthroplasty, facilitating a more rapid recovery. There are currently no published results of randomised clinical trials comparing the two arthroplasty techniques. The primary objective of the current study is to assess whether there is a difference in functional knee scores and quality of life outcome assessments at one year post-operation between patellofemoral arthroplasty and total knee arthroplasty. The secondary objective is to assess the complication rates for both procedures.
Methods/design
Patients who are deemed suitable, by an Orthopaedic Consultant, for patellofemoral arthroplasty and medically fit for surgery are eligible to take part in this trial. The consenting patients will be randomised in a 1:1 allocation to a total knee or patellofemoral arthroplasty. The randomisation sequence will be computer generated and administered by a central independent randomisation service. Following consent, all participants will have their knee function, quality of life and physical activity level assessed through questionnaires. The assigned surgery will then be performed using the preferred technique and implant of the operating surgeon. The first post-operative assessments will take place at six weeks, followed by further assessments at 3, 6 and 12 months. At each assessment time point all complications will be recorded. In addition, community and social care services usage will be collected using a patient questionnaire at 3, 6 & 12 months. The patients will then be sent an annual postal questionnaire. The questionnaire will ask about any problems, knee pain and function following their knee arthroplasty to monitor long-term function and failure rates.
Discussion
This trial is expected to deliver results in early 2013
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